To produce large-scale and high-performance devices including LSI (Large Scale Integration), an ultrafine pattern is required. Such a pattern is a resist pattern formed through exposure, development, and washing (rinsing), or an etching pattern formed through etching and washing (water-washing).
A resist is a polymer material which is photosensitive to light, X-ray, and electron beam, and exposure is performed by irradiating the resist with light or electron beam through a mask having a pattern formed based on circuit design.
When a photosensitive resist film is exposed, the molecular weight and molecular structure of the exposed area vary to cause a difference in solubility in a developer between the exposed area and the unexposed area, and thus a photosensitive resist pattern can be formed by a development treatment utilizing a difference in solubility.
Using this resist pattern as a mask, an insulation film and a conductive film formed on the substrate are partially etched, the unnecessary resist pattern is removed, and thus transfer of the pattern onto the substrate is completed.
A conventional resist is described in Patent Reference 1.
In the formation of a photosensitive resist pattern, a resist requires various properties, in which (1) sensitivity, (2) pattern size controllability, and (3) etching resistance are recently considered to be particularly important.
(Patent Reference 1)
Japanese Unexamined Patent Application, First Publication No. 2002-341538
(Non-Patent Reference 2)
Applied Physics Letters, Vol. 63, page 764, 1993